Mechanism for and improved method of forming pulp articles



Apnl 17, 1934. A. w. MORRIS 1,955,249

MECHANSM FOR AND IMPROVED METHOD OF' FORMING PULP ARTICLES Filed March 29, 1932 2 Sheets-Sheet l MMMMLWL/w l 1| INVENTOR.

2S BY @qw A TTORNEYS.

April 17, 1934.

A. w. MORRIS MECHANISM FOR AND IMPROVED METHOD OF FORMING PULP ARTICLES Filed March 29, 1932 2 Sheets--Sheel 2 A TTORNEYS.

I Patented Apr. 17, 1934 MECHANISM FOR AND IMPROVED METHOD OF FORMING lPULP ARTICLES Albert Wood Morris, Philadelphia, Pa., assigner to George E. Coblens, New York, N. Y.

Application March 29, 1932, Serial No. 601,744

8 Claims.

My invention relates to a new and improved mechanism for and a new and improved method of forming pulp articles.

One of the objects of my invention is to provide improvements on U. S. Patents Nos. 1,739,766 and Another object oi.' my invention is to provide a new and improved molding device for molding objects such as bottle protectors and the like,

10 which have relatively deep depressed portions.

Another object of my invention is to improve the molding of receptacles made of cellulose or similar products'.

Other objects of my invention will be set forth in the fol-lowing description and drawings which illustrate a preferred embodiment thereof, it being understood that the above general statement of the objects of my invention is intended merely to generally explain the same and not to limit it in any manner.

Fig. 1 is a plan View.

Fig. 2 is a sectional view on the line 2-2 of Fig. 1.

Fig. 3 is a sectional view on the line 3-3 ofv Fig. 1.

Fig. 4 is a detail view showing a pair of th mold members in operative position with thepulp between them.

Fig. 5 is a sectional view on the line 5-5 of Fig. 6.

' Fig. 8 is a sectional view of a second embodiment of the apparatus'.

Fig. 9 is a sectional view on the line 9-9 of Fig. 8. v 40 Fig. 10 is a sectional view of a third embodiment of the apparatus.

Fig. 11 is a sectional view on the line 11--11 of Fig 10. 1

In said previously issued U. S. patents, I have disclosed the use ofv a heated screen member or screen members in order to mold anarticle from cellulose material of the kind usually designated as pulp. This pulp material has been used for many years in forming pie plates and receptacles of various kinds.

In order to form a receptacle such as a berrybox, a bottle protector or the like, it is necessary to form the mold members with relatively deep depressions, and such depressions are frmuently 5 irregular. It isdiiiicult to iorm such mold mem- M are made of suitable heat resistant material,

ters A, B. C, D and E in Fig. 1, in order to perbers from wire screens, especially if the wire is made of a nickel chromium alloy of the heatresistant type, thisl type being designated in the trade as yl\llichrome.

According to the present invention, the mold members are made of separated and suitably insulated metal members, which are preferably made of nichrome or similar material so that molds of any size and shape can be conveniently formed.

In the first embodiment, illustrated in Figs. 1-5 inclusive, a pair of cooperating mold members are shown. Since the male mold member and the female mold member are of substantially similar construction, the same description 7o applies to both. l

As shown more particularly in Fig. 3, the female mold member comprises a frame 1, having opposite end members which are connected by means of one or more bolt members 2. These bolt members 2 are passed through the bases of the molding elements M and through sheets of insulating material 3, by means of which said molding elements M are separated. Said molding elements S0 such as a nickelv chromium alloy which can be heated to relatively high temperatures. Material of` this type is well known under the name oi.' nichrome. 'I'he molding elements M and the intermediate sheets of insulating material 3 are held tightly clamped within the frame 1, by means of the bolts 2. The sheets of insulating material 3 may be made of mica or other suitable material. 'I'he clamping frame 1 may be made in two pieces if desired, and these two pieces can' be forced against each other by means o f the bolts 2, in order to tightly clamp the molding elements and the sheets of insulatingmaterial within the frame. The frame 1 may rest upon any suitable support S.

The metal molding elements M can be provided with grooves or depressions 5a, and the sheets 3 may be provided with corresponding grooves or depressions 5b. When the parts are assembled, the grooves 5a. and 5b register with each other. in order to form continuous grooves 5 which extend from one end of the molding member to the other. The frame 1 is provided with corresponding holes 5d so that thevaporized moisture can readily escape from the device when the device is being used.

The metal molding elements M and/or the insulating elements 3 may be undercut at specifled intervals. as indicated by the reference letmit the moisture to escape laterally into the grooves 5.

As shown in Figs. 3 and 5, the insulating elements 3A have theirr surfaces a little below the surfaces of the metal elements M so that the sheet of molded pulp is formed with corrugations. The molding device is thus provided with depressions 3a so that the bottom of the sheet of pulp P is formed with ribs 8 and with depressions 8a. The other surface of the pulp is likewise formed with ribs 9` and with depressions 9a, as indicated in Fig. 6.

The female mold member is provided with a pair of bus-bars '1, one of which is shown in Fig. 2, the other bus-bar being similarly disposed at the opposite edges of the metal members M'. If said bus-bars are connected to a suitable source of direct current, or to a suitable source of al- .y .ternating current, the current passes through the metal members M, in order to heat same to the required temperature for drying and setting the moist material.

As shown in Fig. 6, the sheet of molded pulp P can be of any size, and a plurality of depressions can be formed therein. These depressions are separated by intermediate planar portions 11.

Each of the depressed portions 10 is adapted to receive the bottle to be protected. Of course, the shapes of the depressed portions 10 can be varied in order to correspond with the shape of the fragile article to be protected. Such articles may include eggs, incandescent lamp bulbs, etc.

As shown in Fig. 4, the male member of the mold is provided with metal molding elements Ma which correspond to the metal molding elements M, and the male molding member is provided with tie-bolts 2a which correspond to the bolts 2. The male molding member vis also provided with a pair of bus-bars 7a which correspond infunction to the bus-bars 7. The bus-bars "la can be connected to a suitable source of current, either direct or alternating, in order to heat the members Ma. 'I'he elements of the male molding member are likewise provided with grooves or depressions 5c, which register with the depressions l5a formed in the elements'of the female molding member, in order to provide continuous grooves for permitting the escape of moisture, when the cooperating mold members are in operative position.

As pointed out in the previously issued patents, the pulp -is subjected to the action of the molding members while said molding members are heated by velectricity or by other means.

In order to mold the pulp device, a layer of pulp materal P is placed upon the ends of the molding elements of the female mold, and the male molding member is then applied with suitable pressure, so as to force out as much moisture as possible by means. of mechanical pressure. The water can escape laterally through the channels A, B, C, D and E, and it can then escape longitudinally through the grooves 5. Of course, the male molding member can be supplied with lateral channels corresponding to the channels A, B, C, D and E. One of the busbars I and its corresponding or superposed busbar 'la may be connected to the same terminal 4 of the dynamo. For example, if a direct current is used, one pair of bus-bars 'I and 7a may be connected to the positive terminal of the dynamo, and the other pair may be connected to the negative terminal. Since the superposed bus-bars are always of the same polarity, there is no danject beyond the sheets of insulating material 3.

Referring to Fig. 5, the insulating members 3 extend almost to the tops of the conducting plates M. The metal plates M are therefore reinforced almost to the tips thereof. However, the invention is not to be limited to this feature and the longitudinal drainage channels 5 can be formed by suitably recessing the metal plates M, or the metal plates Ma. Said metal plates form assembled elements in the respective male and female mold members.

In the apparatus shown in Figs. 8 and 9, the female mold member is of conical shape, and it is provided with a solid wall having lateral openings or perforations 14, and also having longitudinal recesses or grooves 15. The male molding member 16 is associated with a coil C which is made. of nichrome or other suitable material.

In operating this device, the layer of pulp P is formed upon the inner wall of the female mold member 2l, and coil C is placed in position with little or no pressure, and the member 16 is then forced into position. The member 16 increases the diameter of the turns of the coil C, so that the coil C is forced into the pulp P, so as to produce the effect described in the previously issued patents. The coil C is then heated by means of any suitable current or other lsource of heat. 'I'he current supplied to the coil C may be a direct current or an alternating current. 'I'he pulp is therefore heated by means of the coil C which is pressed into the adjacent surface of the pulp. In actual practice the coil C is practically imbedded in the pulp when said coil is heated.

When the-pressure is applied, the moisture can escape through the channels 15 and 14, and when the heat is applied, the vaporized moisture can likewise escape.

As shown in Fig. 9, the conical molded member which is thus formed is provided with longitudinal ribs which strengthen the same.

In the embodiment shown in Figs. l0 and ll, the coil C is wound upon the outside of the male molding member 17 whichv is suitably grooved ,for this purpose. Hence, the male molding mem- It will be noted that the molding members de-v scribed herein are rigid and non-reticulated.

Referring to Fig. 8, the members 16 and C may be considered as forming an associated molding member. Likewise, in each embodiment means are disclosed for applying heat between the mold members, in order to heat the intermediate layer of pulp.

The members 16 and 17 may be made of any suitable rigid insulating material. The pulp may lili be applied by suction to theinner face of the mold. It will be noted that the various embodiments are adapted to apply heat directly to the pulp, intermediate the surfaces of the molding members.

In actual practice, the pulp will not ll up the depressions which are located between the metal molding members which are illustrated in Fig. 5, or in the other embodiments. When the pulp is shaped under pressure, a felting action will taire place so that the surfaces of the pulp will be formed with regular rounded and wave-like ribs and depressions.

The depressions or grooves between the mold metal members may be madev narrow, so that when the pulp is compressed, it will enter but not fill up said grooves. This makes it possible for water and vapor to escape from the pulp. The representation of the ribs and depressions in the drawings is conventional, and in actual practice, said ribs and depressions which are formed in the pulp will not have the rectangular cross-section which is depicted for example in Fig. 5.

The device may include any desired number of the lateral channels A-E. For example, suchl -channels may be provided in every alternate member of the mold. l

I have shown a preferred embodiment of my invention, but it is clear that numerous changes and omissions can be made without departing from its spirit.

I claim:

1. A mold member comprising plates made of conducting material, insulating members located intermediate said plates, means for holding said plates and the intermediate insulating members in assembled relation, said plates and said insulating members having aligned depressions' in` their outer faces, so as to `form a longitudinal drainage channel, and means adapted to connect said plates to a source of electric current.

2. A mold member comprising plates made of conducting material, insulating members located intermediate said plates, means for holding said plates and the intermediate insulating members in assembled relation, said plates and'said insulating members having aligned depressions in their outer faces, so as to form a longitudinal drainagechannel, certain of said assembled elements being undercut at specified lateral intervals yin order to form lateral drainage channels which communicate with said longitudinal drainage cha'nnel, and means adapted to connect said plates to a source of electric current.

3.- A mold member comprising plates made of conducting material, insulating members located intermediate said plates, the tops of said insulating members being located below the tops of said plates, the spaces between said plates being suiciently large to permit the material to enter said spaces so'that said material is formed with ribs and depressions, and means adapted to pass a current through said plates in order to heat said plates.

4. In combination, a male mold-member and a female mold member, each said mold member comprising a series of plates madeof` conducting material and having intermediate insulating members, means for holding the plates and the intermediate insulating members in each mold member in assembled relation, the assembled elements in each mold member being formed .with grooves which are arranged in superposed pairs when said mold members are in their operative position, said vgrooves then forming longitudinal drainage channels, and means adapted to connect said plates to a source of electric current.

5. In combination, a male mold member andina female mold member, ea'ch said moldl member comprising a, series of plates made of .conducting material and having vintermediate insulating members, means for holding the plates and the intermediate insulating members in each mold member in assembled relation. the assembled elements in each mold member being formed with grooves which are arranged in superposed pairs when said mold members are in their operative position, said grooves then'forming longitudinal drainage channels, said elements being also undercut at specified lateral intervals so asV to form lateral drainage channels Vwhich communicate with said longitudinal .drainage channels, and means adapted to connect said plates to ar source of electric current.

6. A mold member for molding pulp comprising assembled and spaced plates made of conducting material, and-means for passing an electric cursaid plates being suiliciently spaced in order to allow the pulp to enter the spaces between the plates, in order to produce spaced ribs in the molded pulp article. f

7. A mold member for molding pulp comprising assembled and spaced plates made of conducting material, said plates being suiliciently spaced in order to allow the pulp to enter the spaces between the plates, in order to produce spaced ribs in the molded pulp article, and means adapted to connect said plates to a source oi, electric current.

8. A mold member for molding pulp comprising plates made of conducting material, said plates being spaced from each other, the spaces between said plates being sufficiently wide to allow the pulp to enter said spaces so that ribs are formed in the pulp article, the molding edges of said plates being formed with recesses, and means adapted to connect said plates to a source of elec-4 

